This study investigated the variables that shaped people's willingness to engage in collective action in the context of the Occupy Movement. Data were collected in 2011 from nonprotesting supporters at the New York City Occupy encampment and active occupiers at the New York and Atlanta encampments. Participants distinguished between different kinds of collective action based on cost. Furthermore, different predictors motivated distinct kinds of collective action. Identity and anger predicted low‐cost collective action. Efficacy predicted relatively costly collective action and mediated the link between identity and costly collective action. This study provides evidence that people draw distinctions between different actions based on cost and that, when it comes to predicting collective action, these distinctions matter.